ligo/src/lib_p2p/p2p_maintenance.mli
2018-05-03 16:03:01 +02:00

51 lines
2.1 KiB
OCaml

(**************************************************************************)
(* *)
(* Copyright (c) 2014 - 2018. *)
(* Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* All rights reserved. No warranty, explicit or implicit, provided. *)
(* *)
(**************************************************************************)
(* min <= min_threshold <= min_target <= max_target <= max_threshold <= max *)
(** P2P maintenance worker.
The P2P layer urges the maintainer to work when the number of
connections reaches `max` or is below `min`. Otherwise, the
maintener is lazy and only looks up for connections every two
minutes (hardcoded constant). The [maintain] function is another
way to signal the maintainer that a maintenance step is desired.
When the maintener detects that the number of connections is over
`max_threshold`, it randomly kills connections to reach
`max_target`.
When the maintener detects that the number of connections is below
`min_threshold`, it creates enough connection to reach at least
`min_target` (and never more than `max_target`). In the process, it
might ask its actual peers for new peers. *)
type bounds = {
min_threshold: int ;
min_target: int ;
max_target: int ;
max_threshold: int ;
}
type 'meta t
(** Type of a maintenance worker. *)
val run: bounds -> ('msg, 'meta) P2p_pool.t -> 'meta t
(** [run ~greylist_timeout bounds pool] is a maintenance worker for
[pool] with connection targets specified in [bounds]. *)
val maintain: 'meta t -> unit Lwt.t
(** [maintain t] gives a hint to maintenance worker [t] that
maintenance is needed and returns whenever [t] has done a
maintenance cycle. *)
val shutdown: 'meta t -> unit Lwt.t
(** [shutdown t] is a thread that returns whenever [t] has
successfully shut down. *)